Inner Ninja
by Keefer
Summary: The main target slept soundly in their bed before them. His back was turned to the attacker, slowly rising and falling with deep breaths, as he remained oblivious to the other presence in the room.


**A/N: I truly had the weirdest thought while writing this story. What if Natsu farted flames? Honest to God, what if he did? That would just be the greatest thing ever! Just going on a mission, fighting the bad guys, when suddenly BOOM! Flames erupt from Natsu's ass and everyone is appalled and stunned while he's just like, 'Eh, happens all the time' and knocks everyone out while they are trying to understand what they just saw. Food for thought.**

**Anyway, Natsu and Gray are ten in this story. That means that Happy isn't around yet. And it does do a kind of whiplash from cute to wham bam pow! Stick it in now! So enjoy!**

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The robed figure silently padded down the hallway, his breath soft as he swiftly flew from passageway to passageway. His route was planned out meticulously, not a single person lay between him and his target. The sounds of a door opening at the end of the hallway had the form freezing, pressed against the wall as it became completely still. The echoing footsteps slowly fading into the distance, the silence forming once again before the shape started moving towards its goal.

The room at the end of the hallway was the target, the door smooth as it swung open on its hinges. The form slipped into the room, the door closing behind the black shape. With a billow and puff of air the figure opened a window, sliding through the opening before returning the glass to where it had been previously. Balancing on the miniscule edge lining the side of the guild the form slowly made it's way towards the window around the corner, the pane already cracked open to let the fresh spring air into the room.

The cloaked figure paused, listening for the smallest noise or sign that he had been caught. Taking a deep breath the form slipped in the room, moving instantly to the corner shadow, hiding the lithe form in the dark shadow of the growing sunrise. There was a limited amount of time before the hiding place would be revealed, the morning light threatening the entire plan.

The figure stopped, eyes closed and body calm. Taking a moment they started recited to themselves_, __Assassin's rule number one - silence: dissolve in the darkness and erase your breath. Wait for an opening to attack your target._ Eyes sprung open, shining faintly in the growing light. Taking light steps forward the form stayed as low to the ground as they could, staying close to the wall as not to draw attention directly to themselves._ Assassin's rule number two - transpositional thinking: Analyze the target in order to predict his thoughts and movements._ The form was at the center point of the room now, the main target sleeping soundly in their bed before them. His back was turned to the attacker, slowly rising and falling with deep breaths, as he remained oblivious to the other presence in the room. _Assassins rule number three - speed: take out the target before the target notices your presence._

The form grinned, teeth pointed and shinning before attacking. Jumping straight up in the air the body landed directly on the sleeping boy, blue eyes flying open in surprise as a cry emanated from his lips. The boy looked around the room in a panic, his heart threatening to beat out of his chest with how hard it was pounding. The boy's eyes widen, panicked and frenzied, before finally landed on the pink haired boy rolling around the floor in laughter, tears streaming from his eyes.

"Natsu…" Gray growled, his hands tensing on the sheets beneath them. The pinkette only starting to laugh harder, his breath coming in gulps as tears ran down his face.

"You," gasp, "should," pant, "have seen," chuckle, "your," breathless giggling, "FACE." It was at that point that Natsu began laughing so hard that no noise came from his throat, the tears coming from his eyes forming puddles beneath his head.

Gray growled, his teeth bore as he yelled, "What are you even doing in my room charcoal?"

That snapped Natsu out of his laughter, the boy hoping to his feet instantly as he struck a pose, "I'm a Ninja."

Gray eyed the boy up, the scarf that Igneel gave him wrapped around his head, slight tuffs of pink hair sticking out between the folds. The boy was standing with his feet parted, arms straight out and moving from stance to stance, each movement accented with a 'oooooooo-' or 'waah!'. The boy raised an eyebrow, his arms crossed as he stated, "A ninja?"

Natsu nodded, crouching low to the ground as he replied, his tone deathly serious, "Yes. The child of darkness and shadows, a deadly assassin that none can catch. Blending into the background I can vanish without a thought."

Gray furrowed his brow, the other boy getting on his nerves, "And you attacked me why?"

Natsu paused his stance, the boy balancing on one foot, the other curled up and ready for a quick kick. His hands were raised above his head in a manner that could only resemble a crow ready for take off. Gray could barely manage to stifle a laugh at the other boy's completely ridiculous form. Natsu, oblivious to his appearance said simply, "Elfman and Cana are no fun to attack, Elfman just cries and Cana knows that you're coming. Erza and Mirajane would kill me, and Lisanna just wants to play house all the time. So that leaves you." The boy then proceeded to jump into the air, kicking out his leg and letting out a loud 'Hu-wah!' as he did so.

Gray watched with amusement for a second before flopping down on his bed and throwing his pillow over his head, "Get out of my room Flame-brain."

Natsu watched as Gray threw the blanket over his form, the lump on the bed moving as the dark haired boy buried himself into the pile of sheets. Natsu narrowed his eyes, crouching down with one hand on the floor before pushing off with a cry, landing on the pile hard. Yanking the covers back Natsu looked down on Gray, the other boy clutching his stomach, trying his hardest to regain the breath that had been so forcefully removed from his body. "Come on freezer-burn, we can be ninja's together!"

Gray looked up at the boy, curled up on his side to protect the rest of his vital organs from the onslaught of the former. Calculating his response Gray answered warily, "If I join you, will you leave me alone after?"

Natsu grinned, his eyes closing as he replied, "Yep!"

Gray sighed, pushing the other boy off of not only himself, but the bed as well. Standing up slowly Gray turned to face the other, stretching as he inquired, "What do you want me to do?"

Before he realized what was happening, Natsu had one of Gray's shirts in his hands, forcing the article of clothing over his head and wrapping it around his head several times, the black hair sticking out in the same style as Natsu's. The blue-eyed boy let out a cry of exclamation, hands going instantly to his head to take off the makeshift ninja mask. They didn't make it that far though as Natsu instantly slapped them away, his face downcast as he scolded, "What kind of ninja doesn't have a mask?"

Gray sighed, letting his arms drop to his sides. Unconsciously he started to take his pants off, Natsu paying no attention to the fact that Gray was starting to strip. Gray let his pants drop to the floor, his gaze not leaving Natsu's eye, as he required, "So what's our mission?"

Natsu grinned, grabbing Gray's hand and pulling him out of the room and down the hallway to the guildhall. Dragging him into the shadow of the doorway he pointed into the room, whispering so low Gray could barely hear him, "To piss off as many people as we can."

Gray smiled, his eyes flashing as he agreed, "Let's do this hot-head."

The boy's were silent as the moved throughout the hall, neither seen as they made their way from person to person. The pranks that they pulled were just small; Wakaba's pipe going missing or Reedus' paints tipping over when his back was turned. No one ever caught the boys in the act, but there was no denying that it was the two of them who were performing the tricks. Faint laughter could be heard as the boy's ran away, their last event of the day resulting in Elfman in tears and Mirajane swearing to kill the two boys.

The two ran from the hall, their laughter echoing up and down the barren halls as their feet took them to the store rooms, both falling to the ground panting with smiles on their faces. Natsu turned to Gray, his eyes shining with joy as he said, "Icicle, you are now an official Ninja."

Gray smiled at the roof, the thrill of the game still lingering in his veins, "Let's do that again sometime."

Natsu turned his eyes to the ceiling, "Anytime Gray."

That anytime appeared eight years later in the form of Natsu waiting for Gray in their room, the pinkette clinging to the rafters of the ceiling with an evil glint in his eyes. He had been waiting for Gray to arrive for ten minutes now, his arms and legs starting to strain from the effort. His goal was simple enough, an easy attack from the roof when Gray entered the room. A quick drop from the ceiling onto Gray would result in his victory, sweet and swift.

The opening of the door had Natsu grinning, his plan coming together before his eyes. He watched with predatory precision, the tussled mop of black hair slowly coming through the door, calling out as he did so, "Thanks Wendy! I'll see you tomorrow!"

The elder shut the door behind him, standing there for a fraction of a second before stating, "I know you're there Cinderella."

Natsu gritted his teeth, growling slightly as he dropped from the roof, throwing his arms out to catch Gray as he plummeted to the floor. The Ice Mage was faster though, moving a step to the side and avoiding Natsu's attack completely. The Dragon Slayer hit the floor hard, the belly flop in perfect form. Natsu curled in on himself instantly, groaning at the force of the hit.

Gray chuckled as he walked over to the dresser, flinging the doors open as he moved to remove whatever clothing he was still wearing, "When are you going to learn ember? I know if you're in a room or not." Casting a smirk over his shoulder he remarked, "There's a faint burning smell."

Natsu glared right back at the other; "It's better than smelling like a blizzard all the time."

Gray turned to Natsu, clad in only his boxers with his arms crossed against his softly sculpted abs, "Blizzard's don't smell like anything."

Natsu grunted, rising to his feet as he worked off the pain, "They smell like the cold."

Gray opened his mouth to reply but decided against it, moving to lounge on the bed instead. Natsu followed him, flopping onto the bed beside Gray. Rolling onto his stomach Natsu cradled his chin in his palm, the other hand going to poke Gray repeatedly in the side. Gray glanced down at the hand currently pressing into his flesh just a little too hard before gently slapping it away, "What were you doing any way?"

Natsu grinned at the older, the childish mischief he never lost gleaming from his face, "Being a Ninja."

Gray scoffed, sitting up on his elbows as he questioned, "Really now?" With a quick push Gray moved on top of Natsu, covering the younger teen with his body, "And what would happen to said Ninja if he was caught?"

Natsu tilted his head, eyes rolling up as he started to think, "Probably killed I guess."

Gray leaned his head down, slowly running his lips over Natsu's collarbone as he said, "Not tied down and then tortured?"

Natsu huffed, shrugging slightly as he argued, "That's possible, but I really think-" His sentence cut off with a startled gasp as his arm's were forced above his head, the scarf that was once wrapped around his neck now binding his wrists to the headboard, "Gray? What are you doing?"

Gray lifted his eyes, his tongue flicking out from his mouth to swipe over the base of Natsu's throat, "I've caught a Ninja, and he needs to be punished."

Natsu's eyes widened when he caught on to what Gray was saying, his wrists twisting in his scarf as he tried to pull away from the headboard, "Gray…"

The teen stopped, lifting his head to look Natsu dead in the eye, "What Natsu? You want me to stop?"

Natsu turned his head, blushing as he mumbled, "No, but…"

Gray waited for the continuation of the sentence, but when Natsu made no effort to finish Gray prompted him, "But what?"

Natsu finally turned to look at Gray, his eyes pleading as he did so, "But if the attack didn't work, shouldn't I not be punished?"

Gray shook his head slightly, ducking down to nip at the tender flesh of Natsu's underarm, "All the more reason to punish a lousy Ninja." With that said Gray bit down, Natsu letting out a shocked gasp, which quickly melted into a moan as Gray sucked on the punished flesh.

The icy cold of Gray's lips soothed the fire beneath Natsu's skin, the contrast never failing to send shivers coursing through his body. Tonguing up Natsu's arm Gray made his way to the Dragon Slayer's fingers, slowly slipping each one individually into his mouth. His tongue encased each one, circling and dipping between each digit, coating each one before moving onto the next.

Natsu was enthralled with watching Gray, the other's actions always holding a certain level of fascination with the fire-eater. Each movement that he made was thought out and crafted, an art form that Natsu could never get enough of. Gray could feel Natsu's eyes on him, the pressure of that gaze pushing him farther. Straddling Natsu's waist, Gray sat down, rolling his hips against the other teen's groin as he did so. The tension seeped from Natsu's body as Gray continued, his form melting under the touch of the Ice Mage.

Settling lower on Natsu's body Gray continued turning his hips, grinding hard on the other in practiced figure eights. Ghosting cool breath on Natsu's neck, Gray pressed light kiss after kiss along the overly sensitive flesh of the boy's throat. His tongue came into play soon after, licking wet stripes up to Natsu's jaw, freezing the saliva just enough to contrast the heat emanating from the pinkette's flesh. The needy moan coming from Natsu had Gray humping his lower half, lips attacked to the younger jaw as he sucked a dark bruise into his skin.

Pulling away panting, Gray looked up at Natsu, both of their eyes blown wide open and begging. Gray didn't need to hear the words from Natsu's mouth before he was sliding down the bed, hands skillfully opening the belt that held Natsu's pants up. The carefully selected fabric fluttered to the floor, leaving the Dragon Slayer in nothing but his vest.

Placing himself between Natsu's legs, Gray bent down, his slender fingers moving to trace nothingness on Natsu's thighs as his mouth went straight for the teen's balls. Natsu gasped, the cool of Gray's mouth encasing him and numbing each sensation, replacing them with pure ecstasy. Chest tightening, Natsu bucked down, his body moving with a mind of it's own. Gray pulled back, tutting slightly as he moved to the teen's thighs instead.

The whine that Natsu let out had Gray chuckling, "No way Natsu. This is punishment remember?"

Gray could hear the strain of the headboard, the noise more than enough of a reply. With a smile he began to rub the side of his face against the supple inner flesh of Natsu's thighs, his hair tickling the sensitive skin there. He could feel the tensing of the muscle beneath his cheek, the internal battle Natsu fought between remaining where he was and pulling away. Pulling his knee over his shoulder, Gray kissed every inch from his pelvis to knee, hand trailing lightly after his mouth in a soothing caress.

Finishing with the one leg, he moved to the other, repeating the exact same motion. The way that Natsu panted under his touches, the pure unadulterated need that strained his body, had Gray growing harder in his boxers. The way that Natsu reacted to him was all the stimulus that the Ice Mage needed.

Keeping the teen's legs over his shoulder's Gray finally ducked his head down, opening his lips to take the tip of Natsu's cock in his mouth. Running his tongue over the tip he breathed out lightly, freezing the head ever so slightly. Natsu gasped at the sudden cold, flagging a tiny bit at the sporadic temperature change before getting use to the drastic difference. Taking Natsu deeper into his mouth Gray repeated the process, leaving a slight layer of ice behind before melting the coating with the heat of his mouth once again. Over and over Gray did this, finally reaching the base of Natsu's dick and deep throating him in a motion that had taken months of practice. Keeping his tongue wrapped around Natsu's member he could feel the thrumming beat of his heart, powerful and insistent.

Pulling off, Gray started licking whatever he could get his mouth on, his lips leaving behind the barest of frost wherever they touched. Fingers made their way up to Natsu's chest, teasing and pulling on the dusky light nipples that contrasted so beautifully with the tan of the teen's skin. Looking up briefly, Gray met Natsu's eye and winked, waiting a fraction of a moment for Natsu to understand what he was going to do before placing that all familiar chill to everything that he was touching.

Natsu cried out, his body curling up off the bed as his mind erupted with contrasting and confusing sensations; each one more powerful than the last. Gray quickly gripped the base of Natsu's cock, stopping him from climaxing all too soon. Reaching down to the bedroom floor Gray fumbled for the bottle of lube and condom that he knew were there, giving Natsu some time to settle down a little before continuing.

The pop from the bottle cap had Natsu's eyes moving down to Gray; hooded and unfocused they watched as graceful fingers coated themselves in clear liquid, the sight enough to make him drool. Gray placed the bottle beside him, rubbing his fingers together so the cold wouldn't be too much for Natsu. His first finger slid in easily enough, reoccurrences of the process helping smooth it out some. But one thing never changes, the look of utter contentment on Natsu's face whenever Gray was in him. It didn't matter what part of him it was, as long as it was Gray that was all that Natsu needed.

Wiggling his finger around Gray husked, breathing in deep the sent of his lover, "Have you learned your lesson yet Natsu?"

The pinkette nodded, moaning at the addition of a second digit. Gray looked up, spreading his fingers harshly when he didn't get the answer he wanted, "Have you learned your lesson Natsu?"

Natsu tensed, pulling hard against the scarf holding his wrists to the headboard and whined, pushing against the fingers breaching his ass, "Yes Gray, yes yes yes…"

Gray grinned, removing his fingers from Natsu and moving for the package beside him, "Good."

Natsu watched panting as Gray tore open the condom packaging, rolling the latex gracefully onto his dick, drizzling lube on the rubber before quickly running his hand up and down it to make sure the condom was evenly coated. Hoisting Natsu's legs over his shoulder's Gray lined himself up with the other teen's entrance, grasping the fire-eater's hips as he asked once again, "Can I?"

Natsu nodded furiously; mind gone as he begged, "Please, please Gray."

Gray nodded, turning gaze down as he slowly pushed into the Dragon Slayer, muscles straining as he forced his way inside the burning furnace that never cooled down. The process was slow, but Gray finally sunk fully into the burning heat that he could only label as perfect. The flaming pressure was Natsu, and Natsu alone, and Gray loved it.

He waited, panting as he tried to keep his cool while that pressure threatened to tear his very mind away. Natsu finally keened, pressing against Gray, whispering lightly for him to move.

Rolling his hips slightly, Gray started to move, letting Natsu open up for him before slamming back in hard, searching for that one spot he knew was there. When Natsu let out a broken cry Gray knew that he had found it, dropping one of the teen's legs so he could get a better angel. With shallow thrusts Gray repeatedly slammed into Natsu, striking his prostate without mercy. Both teens were mindless, Natsu moaning wantonly as Gray spoke nonsense to him, praising him and telling him time and time again how much he loved him.

Natsu was the first to cum, tears leaking from his eyes as his face bunched up, mouth wide as he cried out. Gray continued slamming into Natsu as he tightened around him, hot strings of cum covering the Dragon Slayers chest. Leaning down Gray licked up a trail, hips stuttering as he climaxed, savoring the taste of Natsu on his tongue.

The feeling of Gray coming within him had Natsu whining, eyes begging for something more from Gray. Meeting the pleading gaze, Gray knew exactly what his partner wanted; leaning up and giving him the most passionate kiss he could muster. He let Natsu lick inside his mouth, the younger tasting the unique mixture of himself and Gray, one that wasn't as awful as he thought it would be.

Refusing to leave Natsu's mouth, Gray pulled out slowly from his body, tying up the condom and tossing it somewhere else in the room. Moving upward Gray blindly untied Natsu's wrists, letting the scarf fall to the floor beside the bed. The moment that his hands were free, Natsu tangled them in Gray's hair, refusing to let the Ice Mage part from him for a second.

Turning his head, Natsu deepened the kiss, his mouth sending shivers down Gray's body, his knees going weak as he tried to remain hovered over the black eyed beauty. The two finally parted, gasping for air as Gray collapsed on the bed beside Natsu. Throwing one arm over the Dragon Slayer, Gray curled up to his side, muttering faintly as his eyes drifted shut, "Did you learn your lesson Natsu?"

The pinkette nodded, tugging Gray closer as he said, "Yeah, never get caught."

Gray huffed, lifting his hand to slap Natsu lightly before saying, "I'll always catch you fire face."

Natsu smiled, cradling Gray's head in his shoulder, "And I'll always let you."

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**A/N 2: Because I couldn't let it end that sappy, continuation of previous farting comment: I told my roommate about that thought and she turns to me and says, 'I bet Natsu sets his poop on fire sometimes by accident'. Of course my mind goes directly to Gray walking into the bathroom and sometime later you can hear him yelling, 'Natsu! The toilet's on fire again!' and spurring an age-old argument that they have far too frequently. Man, I kill myself sometimes. Reviews?**


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